Construction Project Management & Engineering Economics 3rd Stage
Dr. Adnan Fadhil
Assist. Lect. Mustafa Ayad
1
Activity-On-Node (A-O-N) Network Planning Technique
What is the A-O-N Network (Precedence Diagram)?
The Activity-on-Node, or Precedence Diagram uses similar logic to Activity–on-Arrow
(A-O-A), but it is represented differently. With this technique, the activity is
represented by a box or node, with the arrows showing logic relationship between
boxes as shown below:
A-O-N Network Diagram Specification:
– There is no dummy activity.
– All the information that wanted to any activity is written on the box (node) area.
– The time overlapping problem for activities is solved by this technique.
– The delay time for activities can be solved without needing to return to the plan
details.
The Activity Early Start (E.S)
It is the earliest time that an activity can start with.
Construction Project Management & Engineering Economics 3rd Stage
Dr. Adnan Fadhil
Assist. Lect. Mustafa Ayad
The Activity Early Finish (E.F)
It is the earliest time that an activity can finish with.
E.F = E.S + Duration (D)
The Activity Late Finish (L.F)
It is the latest time that an activity can finish with.
The Activity Late Start (L.S)
It is the latest time that an activity can start with.
L.S = L.F – Duration (D)
The Activity Total Float (T.F)
The float for an activity is the amount that its duration can slip without causing the
